Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 41
Filter
1.
Ann R Coll Surg Engl ; 103(9): e288-e291, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33851880

ABSTRACT

Osteoclast-like giant cell tumours of the kidney are extremely rare and usually accompanied by a conventional urothelial neoplasm such as papillary, transitional renal cell, or sarcomatoid carcinoma. Although they have morphological features similar to those of the giant cell tumours in the skeletal system, their counterparts in the urinary system show highly malignant features. Our case is the third primer malignant giant cell tumour of the kidney in the literature. The patient was a 50-year-old male and underwent nephroureterectomy for a mass of 18×14×13cm in his left kidney. However, the patient died in the second month postoperatively as a result of local recurrences and multiple distant metastases. The general condition of the patient deteriorated progressively; hence, he could not have any adjuvant therapy. Having more information about the pathological and clinical findings of these exceedingly rare tumours can help inform treatment steps.


Subject(s)
Giant Cell Tumors , Kidney Neoplasms , Fatal Outcome , Giant Cell Tumors/pathology , Giant Cell Tumors/surgery , Humans , Kidney Neoplasms/pathology , Kidney Neoplasms/surgery , Male , Middle Aged
2.
J Pediatr Urol ; 15(4): 315-321, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31331806

ABSTRACT

INTRODUCTION: Crossed fused renal ectopia is a rare congenital malformation, wherein both kidneys are present unilaterally, with the ureter of the crossed kidney opening into the bladder on the contralateral side. It has varied presentation from incidental detection to renal impairment. In this largest series of crossed fused renal ectopia, the authors assessed the clinical profile of these children and also attempted to shed light on the challenges in the surgical management. METHODS: It is a retrospective study conducted from January 2009 to July 2018, among patients evaluated for crossed fused ectopia, in the Department of Pediatric Surgery, Christian Medical College, Vellore. Electronic medical records of 36 children were reviewed. Imaging modalities and operative interventions were recorded. Results were analyzed. RESULTS: A total of 36 children were found to have crossed fused ectopia, with male preponderance. Most children presented within one year of age with urinary tract infection being the commonest cause. The most common associated anomaly was anorectal malformation. Ultrasound abdomen and pelvis, micturating cystourethrogram, and radionucleotide scans were the imaging modalities preferred for diagnosis and follow-up. Left-to-right ectopia was more common with inferior ectopic variant being the most common. The predominant urological problems include pelviureteric junction obstruction, vesicoureteric junction obstruction, and vescioureteric reflux. Ureteric re-implant was the most common surgery performed followed by pyeloplasty. Pelvi-pelvostomy, uretero-ureterostomy, bladder augment with Mitrofanoff, and other procedures were performed for select cases. CONCLUSION: Crossed fused renal ectopia is a challenging entity which requires individualized management plans based on the predominant urological anomaly and the functional status. Surgical options are diverse and are guided toward the symptomatic urological problem with focus on preserving the renal function. The long-term prognosis is good in these children.


Subject(s)
Kidney Diseases/congenital , Kidney/abnormalities , Urologic Surgical Procedures/methods , Child , Humans , Kidney Diseases/diagnosis , Kidney Diseases/surgery , Ultrasonography , Urography
3.
Med J Armed Forces India ; 72(Suppl 1): S185-S188, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28050109
6.
Phys Med Biol ; 59(15): 4411-26, 2014 Aug 07.
Article in English | MEDLINE | ID: mdl-25049221

ABSTRACT

Prostate cancer, one of the most common forms of cancer among men, can benefit from recent improvements in positron emission tomography (PET) technology. In particular, better spatial resolution, lower noise and higher detectability of small lesions could be greatly beneficial for early diagnosis and could provide a strong support for guiding biopsy and surgery. In this article, the impact of improved PET instrumentation with superior spatial resolution and high sensitivity are discussed, together with the latest development in PET technology: resolution recovery and time-of-flight reconstruction. Using simulated cancer lesions, inserted in clinical PET images obtained with conventional protocols, we show that visual identification of the lesions and detectability via numerical observers can already be improved using state of the art PET reconstruction methods. This was achieved using both resolution recovery and time-of-flight reconstruction, and a high resolution image with 2 mm pixel size. Channelized Hotelling numerical observers showed an increase in the area under the LROC curve from 0.52 to 0.58. In addition, a relationship between the simulated input activity and the area under the LROC curve showed that the minimum detectable activity was reduced by more than 23%.


Subject(s)
Image Processing, Computer-Assisted/methods , Positron-Emission Tomography/methods , Prostatic Neoplasms/diagnostic imaging , Humans , Limit of Detection , Male
9.
Article in English | MEDLINE | ID: mdl-18230374

ABSTRACT

The use of osseointegration for bone anchorage in the prosthetic management of craniofacial defects has been successfully applied for many years. Different methods can be used for reconstruction of the aural atresia. Nowadays plastic surgery for auricular reconstruction and the bone-anchored episthesis are used for correction of aural atresia. There have been several studies in the literature comparng these techniques. According to those studies, bone-anchored episthesis is an excellent alternative to plastic reconstructive surgery of the auricle. In the present study we present 2 cases with different etiologic factors. The patients' right external ears were absent. There was loss in hearing function in one of the patients. We applied external ear episthesis with a bone-anchored system.


Subject(s)
Ear, External , Plastic Surgery Procedures , Prostheses and Implants , Prosthesis Implantation/instrumentation , Adult , Ear Deformities, Acquired/rehabilitation , Humans , Male , Mastoid/surgery
10.
Med Phys ; 34(10): 3987-95, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17985644

ABSTRACT

Imaging dopamine transporters using PET and SPECT probes is a powerful technique for the early diagnosis of Parkinsonian disorders. In order to perform automated accurate diagnosis of these diseases, a channelized Hotelling observer (CHO) based model was developed and evaluated using the SPECT tracer [Tc-99m]TRODAT-1. Computer simulations were performed using a digitized striatal phantom to characterize early stages of the disease (20 lesion-present cases with varying lesion size and contrast). Projection data, modeling the effects of attenuation and geometric response function, were obtained for each case. Statistical noise levels corresponding to those observed clinically were added to the projection data to obtain 100 noise realizations for each case. All the projection data were reconstructed, and a subset of the transaxial slices containing the striatum was summed and used for further analysis. CHO models, using the Laguerre-Gaussian functions as channels, were designed for two cases: (1) By training the model using individual lesion-present samples and (2) by training the model using pooled lesion-present samples. A decision threshold obtained for each CHO model was used to classify the study population (n = 40). It was observed that individual lesion trained CHO models gave high diagnostic accuracy for lesions that were larger than those used to train the model and vice-versa. On the other hand, the pooled CHO model was found to give a high diagnostic accuracy for all the lesion cases (average diagnostic accuracy = 0.95 +/- 0.07; p < 0.0001 Fisher's exact test). Based on our results, we conclude that a CHO model has the potential to provide early and accurate diagnosis of Parkinsonian disorders, thereby improving patient management.


Subject(s)
Parkinsonian Disorders/diagnostic imaging , Parkinsonian Disorders/diagnosis , Algorithms , Automation , Brain/diagnostic imaging , Brain/pathology , Computer Simulation , Dopamine Plasma Membrane Transport Proteins/metabolism , Humans , Models, Biological , Models, Statistical , Models, Theoretical , Normal Distribution , Phantoms, Imaging , Positron-Emission Tomography/methods , Radiography , Reproducibility of Results , Tomography, Emission-Computed, Single-Photon/methods
11.
J Am Soc Mass Spectrom ; 18(1): 152-61, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17055738

ABSTRACT

A new approach for automatic parallel processing of large mass spectral datasets in a distributed computing environment is demonstrated to significantly decrease the total processing time. The implementation of this novel approach is described and evaluated for large nanoLC-FTICR-MS datasets. The speed benefits are determined by the network speed and file transfer protocols only and allow almost real-time analysis of complex data (e.g., a 3-gigabyte raw dataset is fully processed within 5 min). Key advantages of this approach are not limited to the improved analysis speed, but also include the improved flexibility, reproducibility, and the possibility to share and reuse the pre- and postprocessing strategies. The storage of all raw data combined with the massively parallel processing approach described here allows the scientist to reprocess data with a different set of parameters (e.g., apodization, calibration, noise reduction), as is recommended by the proteomics community. This approach of parallel processing was developed in the Virtual Laboratory for e-Science (VL-e), a science portal that aims at allowing access to users outside the computer research community. As such, this strategy can be applied to all types of serially acquired large mass spectral datasets such as LC-MS, LC-MS/MS, and high-resolution imaging MS results.


Subject(s)
Databases, Protein , Nanotechnology/methods , Proteomics/methods , Software , Spectroscopy, Fourier Transform Infrared/methods , Algorithms , Pattern Recognition, Automated/methods
12.
Med J Armed Forces India ; 63(4): 390-1, 2007 Oct.
Article in English | MEDLINE | ID: mdl-27408062
13.
J Dent Res ; 85(6): 510-4, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16723646

ABSTRACT

Using a ligature-induced model in type-2 Zucker diabetic fatty (ZDF) rat and normoglycemic littermates, we investigated whether diabetes primarily affects periodontitis by enhancing bone loss or by limiting osseous repair. Diabetes increased the intensity and duration of the inflammatory infiltrate (P < 0.05). The formation of osteoclasts and percent eroded bone after 7 days of ligature placement was similar, while four days after removal of ligatures, the type 2 diabetic group had significantly higher osteoclast numbers and activity (P < 0.05). The amount of new bone formation following resorption was 2.4- to 2.9-fold higher in normoglycemic vs. diabetic rats (P < 0.05). Diabetes also increased apoptosis and decreased the number of bone-lining cells, osteoblasts, and periodontal ligament fibroblasts (P < 0.05). Thus, diabetes caused a more persistent inflammatory response, greater loss of attachment and more alveolar bone resorption, and impaired new bone formation. The latter may be affected by increased apoptosis of bone-lining and PDL cells.


Subject(s)
Alveolar Bone Loss/etiology , Bone Resorption/physiopathology , Diabetes Mellitus, Type 2/complications , Alveolar Bone Loss/pathology , Alveolar Bone Loss/physiopathology , Animals , Apoptosis/physiology , Bone Resorption/pathology , Cell Count , Diabetes Mellitus, Type 2/physiopathology , Disease Models, Animal , Fibroblasts/pathology , Fibroblasts/physiology , Male , Osteoblasts/pathology , Osteoblasts/physiology , Osteoclasts/pathology , Osteoclasts/physiology , Osteogenesis/physiology , Periodontal Attachment Loss/etiology , Periodontal Attachment Loss/pathology , Periodontal Attachment Loss/physiopathology , Periodontal Ligament/pathology , Periodontal Ligament/physiopathology , Periodontitis/etiology , Periodontitis/pathology , Periodontitis/physiopathology , Rats , Rats, Zucker
14.
Dentomaxillofac Radiol ; 32(3): 173-80, 2003 May.
Article in English | MEDLINE | ID: mdl-12917283

ABSTRACT

OBJECTIVES: To prove the feasibility of a local CT system as a method of CT suitable for use in dentistry. METHODS: Using an experimental set-up consisting of an X-ray source, a turntable and a charge-coupled device (CCD) detector connected to a PC, CT scans were made of a single molar and a dry mandible. Slices were reconstructed using filtered backprojection. An experimental comparison was made between a full CT geometry and a local CT geometry. RESULTS: Horizontal and vertical slices through the mandible were obtained showing the internal structure of a molar and the surrounding bone. The slices show good contrast and details. A computer experiment gave visual evidence that slices obtained by local CT are not substantially different from slices obtained from a full CT set-up with respect to resolution. CONCLUSIONS: Based on the results obtained so far, local CT of dental structures appears to be a promising diagnostic instrument.


Subject(s)
Mandible/diagnostic imaging , Molar/diagnostic imaging , Tomography, X-Ray Computed/methods , Feasibility Studies , Humans , Image Processing, Computer-Assisted/methods , Microcomputers , Radiography, Dental, Digital/methods
15.
Gynecol Oncol ; 80(2): 162-7, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11161854

ABSTRACT

OBJECTIVE: Because external validation of the present models has not been reported, the purpose of the present study was to assess existing diagnostic models that are used to distinguish malignant from benign masses. METHODS: We tested the performance of existing models in a prospectively assembled data set of 170 patients with an adnexal mass. Twenty-one models that have been reported previously were assessed. The models were based on combinations of ultrasound findings, color Doppler tests, CA-125 measurement, age, and/or menopausal status. For each model, we constructed ROC curves and calculated an area under the ROC curve. RESULTS: Of the 170 adnexal masses that were operated on, 30 (18%) were malignant. The area under the ROC curve of 21 models that were externally validated varied between 0.69 and 0.90. We found the performance of the existing models to be inferior to the performance reported in the initial studies. Even models that incorporated multiple diagnostic tools and that were developed using logistic regression models or neural networks had an area under the ROC curve of 0.86 at maximum. In the case where we focused on almost perfect sensitivity, the highest specificities varied between 0.45 and 0.60. CONCLUSION: Although diagnostic models might be of value in the preoperative assessment of the adnexal mass, their diagnostic performance is not as good as that reported in the original publications.


Subject(s)
Adnexal Diseases/diagnosis , Logistic Models , Ovarian Neoplasms/diagnosis , Adnexal Diseases/pathology , Adnexal Diseases/surgery , Adult , Aged , Aged, 80 and over , Diagnosis, Differential , Female , Humans , Middle Aged , Ovarian Neoplasms/pathology , Ovarian Neoplasms/surgery , Preoperative Care , Prognosis , Prospective Studies , ROC Curve , Reproducibility of Results
16.
Eur J Biochem ; 267(19): 6074-81, 2000 Oct.
Article in English | MEDLINE | ID: mdl-10998069

ABSTRACT

Adenoviral gene therapy vectors suffer from the disadvantages of toxicity and immunogenicity associated with the expression of adenoviral genes from the vector backbone. We report here an alternative strategy for gene delivery that utilizes a single component of the adenoviral type 7 capsid, the penton base (Ad7PB). The Ad7PB gene was sequenced and its amino-acid composition was deduced from its nucleotide sequence. The penton was expressed in Escherichia coli as a soluble C-terminal fusion with glutathione S-transferase (GST-Ad7PB) and was purified by single-step affinity chromatography. Both GST-Ad7PB and cleaved (GST-free) Ad7PB retained the ability to fold into pentamers as observed by electron microscopy. GST-Ad7PB was able to bind a synthetic peptide (FK20) derived from the Ad type 7 fiber and retard DNA through a polylysine chain present at the C-terminus of this linker peptide. GST-Ad7PB was an effective cell transfecting agent when assayed on 293 cells. Transfection was not dependent upon the presence of lysosomotropic agents indicating efficient endosome escape capability. Excess of an RGD-containing peptide derived from Ad7PB was able to inhibit transfection indicating specific integrin-mediated uptake of the GST-Ad7PB-FK20-DNA complexes. We propose that Ad7 pentons can be developed into integrin-specific gene delivery agents.


Subject(s)
Adenoviruses, Human/chemistry , Capsid Proteins , Capsid/isolation & purification , Genetic Therapy , Genetic Vectors/genetics , Adenoviruses, Human/genetics , Amino Acid Sequence , Capsid/genetics , Capsid/metabolism , Capsid/ultrastructure , Cells, Cultured , Chaperonin 60/metabolism , Chromatography, Affinity , Epithelial Cells/metabolism , Epithelial Cells/virology , Escherichia coli/genetics , Factor Xa/metabolism , Glutathione Transferase/genetics , Integrins/metabolism , Kidney/cytology , Microscopy, Electron , Molecular Sequence Data , Receptors, Virus/metabolism , Receptors, Vitronectin/metabolism , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/metabolism , Transfection
17.
J Immunol ; 164(3): 1333-9, 2000 Feb 01.
Article in English | MEDLINE | ID: mdl-10640747

ABSTRACT

HIV-1 infection of the brain results in chronic inflammation, contributing to the neuropathogenesis of HIV-1 associated neurologic disease. HIV-1-infected mononuclear phagocytes (MP) present in inflammatory infiltrates produce neurotoxins that mediate inflammation, dysfunction, and neuronal apoptosis. Neurologic disease is correlated with the relative number of MP in and around inflammatory infiltrates and not viral burden. It is unclear whether these cells also play a neuroprotective role. We show that the chemokine, fractalkine (FKN), is markedly up-regulated in neurons and neuropil in brain tissue from pediatric patients with HIV-1 encephalitis (HIVE) compared with those without HIVE, or that were HIV-1 seronegative. FKN receptors are expressed on both neurons and microglia in patients with HIVE. These receptors are localized to cytoplasmic structures which are characterized by a vesicular appearance in neurons which may be in cell-to-cell contact with MPs. FKN colocalizes with glutamate in these neurons. Similar findings are observed in brain tissue from an adult patient with HIVE. FKN is able to potently induce the migration of primary human monocytes across an endothelial cell/primary human fetal astrocyte trans-well bilayer, and is neuroprotective to cultured neurons when coadministered with either the HIV-1 neurotoxin platelet activating factor (PAF) or the regulatory HIV-1 gene product Tat. Thus focal inflammation in brain tissue with HIVE may up-regulate neuronal FKN levels, which in turn may be a neuroimmune modulator recruiting peripheral macrophages into the brain, and in a paracrine fashion protecting glutamatergic neurons.


Subject(s)
Brain/immunology , Chemokines, CX3C/biosynthesis , Encephalitis, Viral/immunology , HIV Infections/immunology , HIV-1/immunology , Macrophage Activation/immunology , Membrane Proteins/biosynthesis , Neurons/metabolism , Neuroprotective Agents/pharmacology , Adult , Animals , Astrocytes/immunology , Brain/metabolism , Brain/pathology , Cell Movement/immunology , Cells, Cultured , Chemokine CX3CL1 , Chemokines, CX3C/administration & dosage , Chemokines, CX3C/physiology , Child , Cytoplasm/metabolism , Encephalitis, Viral/pathology , Endothelium, Vascular/immunology , Gene Products, tat/administration & dosage , HIV Infections/pathology , HIV Seronegativity/immunology , Humans , Male , Membrane Proteins/administration & dosage , Membrane Proteins/physiology , Microglia/metabolism , Microglia/pathology , Monocytes/immunology , Neurons/pathology , Platelet Activating Factor/administration & dosage , Rats , Rats, Sprague-Dawley , Up-Regulation/immunology , tat Gene Products, Human Immunodeficiency Virus
18.
Eur J Biochem ; 245(2): 465-9, 1997 Apr 15.
Article in English | MEDLINE | ID: mdl-9151980

ABSTRACT

Mammalian ribonucleases constitute one of the fastest evolving protein families in nature. The addition of a four-residue carboxyl-terminal tail: Glu-Asp-Ser-Thr (EDST) in human pancreatic ribonuclease (HPR) in comparison with bovine pancreatic RNase (RNase A) could have adaptive significance in humans. We have cloned and expressed human pancreatic ribonuclease in Escherichia coli to probe the influence of the four-residue extension and neighboring C-terminal residues on the biochemical properties of the enzyme. Removal of the C-terminal extension from HPR yielded an enzyme, HPR-(1-124)-peptide, with enhanced ability to cleave poly(C). HPR-(1-124)-peptide also exhibited a steep increase in thermal stability mimicking that known for RNase A. Wild-type HPR had significantly low thermal stability compared to RNase A. The study identifies the C-terminal boundary in the human pancreatic ribonuclease required for efficient catalysis.


Subject(s)
Ribonuclease, Pancreatic/chemistry , Amino Acid Sequence , Animals , Cattle , Circular Dichroism , Cloning, Molecular , Enzyme Stability , Escherichia coli , Hot Temperature , Humans , Molecular Sequence Data , Peptide Fragments/chemistry , Peptide Fragments/metabolism , Protein Conformation , Protein Structure, Secondary , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Ribonuclease, Pancreatic/genetics , Ribonuclease, Pancreatic/metabolism , Structure-Activity Relationship
19.
Vet Hum Toxicol ; 37(2): 126-30, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7631492

ABSTRACT

Groups of 5-6 pregnant F344/N rats were dosed (po) from d 8 to 12 of gestation with 30 or 60 mg purified fumonisin B1 (FB1)/kg body weight, or with a fat-soluble extract of Fusarium proliferatum/corn culture derived from an amount of corn culture that would provide approximately 60 mg FB1/kg. Control rats were dosed with water or corn oil. Food intake was monitored daily during dosing. Fetal bone development was examined after staining with alizarin red, whereas internal organ development was examined in hematoxylin and eosin-stained tissue sections. Although group differences in maternal body weight were not statistically significant, weight was 6% less in dams dosed with 60 mg FB1/kg compared with the control group (p < 0.12). Relative litter weight was significantly suppressed by 60 mg FB1/kg. Ossification of the sternebrae and vertebral bodies was significantly impaired by FB1 treatment. Litters from mothers treated with a fat-soluble extract of F proliferatum/corn culture did not have suppression of weight or impairment of bone development. Fumonisin B1 is fetotoxic to rats by suppressing growth and fetal bone development.


Subject(s)
Fumonisins , Mycotoxins/toxicity , Teratogens/toxicity , Animals , Bone and Bones/drug effects , Bone and Bones/embryology , Moniliformis/chemistry , Rats , Rats, Inbred F344
20.
Lab Anim ; 26(1): 47-52, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1548846

ABSTRACT

Histomorphology of the gastric and intestinal glands was investigated in 19 sexually mature, adult guineapigs by light and transmission electron microscopy. Gastric glands exhibited the cytological characteristics of oxynticopeptic cells capable of both hydrochloric acid (HCl) and pepsinogen secretion. In the literature, occurrence of oxynticopeptic cells in the proventriculus of the domestic fowl (Toner, 1963; Bell & Freeman, 1971) and in the gastric glands of frogs has been reported (Sedar, 1961; Patt & Patt, 1969; Forte & Forte, 1970). It has been claimed by other investigators (Herriot et al., 1938; Long, 1967) that simultaneous secretion of HCl and pepsinogen by a single, not completely differentiated 'pure' cell type, was highly effective for rapid conversion of the zymogen to active enzyme. Under the light microscope with haematoxylin and eosin stain, the protein secreting activity of gastric glands in guineapigs was masked by the HCl secreting activity, thus morphologically resembling the oxyntic cells. Therefore, different cell types, for example protein-secreting peptic cells and the acid-secreting oxyntic cells, could not be distinguished on the basis of their morphology and staining affinity. For histochemical evaluation of the sections with stains-all method, most cells in the gastric glands responded by a positive reaction to protein. Further, protein containing cells were seen in the intestinal glands of the guineapig caecum. The function of this cell type was correlated with caecotrophic food habits of this species.


Subject(s)
Cecum/ultrastructure , Exocrine Glands/ultrastructure , Guinea Pigs/anatomy & histology , Intestinal Mucosa/ultrastructure , Parietal Cells, Gastric/ultrastructure , Animals , Cecum/chemistry , Cecum/metabolism , Exocrine Glands/chemistry , Exocrine Glands/metabolism , Intestinal Mucosa/chemistry , Intestinal Mucosa/metabolism , Microscopy, Electron/veterinary , Parietal Cells, Gastric/chemistry , Parietal Cells, Gastric/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...